[INFO] fetching crate stayalive 0.5.0...
[INFO] checking stayalive-0.5.0 against try#32cb8dc6fdc8140b91f4d17c4883e528db4e7e6d for pr-83312
[INFO] extracting crate stayalive 0.5.0 into /workspace/builds/worker-10/source
[INFO] validating manifest of crates.io crate stayalive 0.5.0 on toolchain 32cb8dc6fdc8140b91f4d17c4883e528db4e7e6d
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+32cb8dc6fdc8140b91f4d17c4883e528db4e7e6d" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate stayalive 0.5.0
[INFO] finished tweaking crates.io crate stayalive 0.5.0
[INFO] tweaked toml for crates.io crate stayalive 0.5.0 written to /workspace/builds/worker-10/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+32cb8dc6fdc8140b91f4d17c4883e528db4e7e6d" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+32cb8dc6fdc8140b91f4d17c4883e528db4e7e6d" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+32cb8dc6fdc8140b91f4d17c4883e528db4e7e6d" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1e809993c48a14397eb17ecbc68331f4e55d4c0d2d1501a9b129d0b3d57aecd3
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "1e809993c48a14397eb17ecbc68331f4e55d4c0d2d1501a9b129d0b3d57aecd3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1e809993c48a14397eb17ecbc68331f4e55d4c0d2d1501a9b129d0b3d57aecd3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1e809993c48a14397eb17ecbc68331f4e55d4c0d2d1501a9b129d0b3d57aecd3", kill_on_drop: false }`
[INFO] [stdout] 1e809993c48a14397eb17ecbc68331f4e55d4c0d2d1501a9b129d0b3d57aecd3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+32cb8dc6fdc8140b91f4d17c4883e528db4e7e6d" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 517dd3b6616a2cd66728a3de10c3dc3a277589ad02885eb3fa37db062c91cde8
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "517dd3b6616a2cd66728a3de10c3dc3a277589ad02885eb3fa37db062c91cde8", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.24
[INFO] [stderr]    Compiling libc v0.2.91
[INFO] [stderr]    Compiling syn v1.0.64
[INFO] [stderr]     Checking adler v1.0.2
[INFO] [stderr]    Compiling failure_derive v0.1.8
[INFO] [stderr]     Checking object v0.23.0
[INFO] [stderr]    Compiling miniz_oxide v0.4.4
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking threadpool v1.8.1
[INFO] [stderr]     Checking backtrace v0.3.56
[INFO] [stderr]    Compiling synstructure v0.12.4
[INFO] [stderr]     Checking failure v0.1.8
[INFO] [stderr]     Checking stayalive v0.5.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/bulkheads/concurrency_limiters.rs:241:19
[INFO] [stdout]     |
[INFO] [stdout] 241 |     exec_cmd: Arc<Fn(C, P::Resource) -> Result<T, E> + Send + Sync + 'static>,
[INFO] [stdout]     |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(C, P::Resource) -> Result<T, E> + Send + Sync + 'static`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/bulkheads/concurrency_limiters.rs:241:19
[INFO] [stdout]     |
[INFO] [stdout] 241 |     exec_cmd: Arc<Fn(C, P::Resource) -> Result<T, E> + Send + Sync + 'static>,
[INFO] [stdout]     |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(C, P::Resource) -> Result<T, E> + Send + Sync + 'static`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: `E` cannot be shared between threads safely
[INFO] [stdout]    --> src/circuitbreakers/mod.rs:9:24
[INFO] [stdout]     |
[INFO] [stdout] 9   | #[derive(Debug, Clone, Fail)]
[INFO] [stdout]     |                        ^^^^ `E` cannot be shared between threads safely
[INFO] [stdout]     | 
[INFO] [stdout]    ::: /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/failure-0.1.8/src/lib.rs:108:42
[INFO] [stdout]     |
[INFO] [stdout] 108 | pub trait Fail: Display + Debug + Send + Sync + 'static {
[INFO] [stdout]     |                                          ---- required by this bound in `failure::Fail`
[INFO] [stdout]     |
[INFO] [stdout]     = note: required because it appears within the type `CircuitBreakerError<E>`
[INFO] [stdout]     = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: consider further restricting this bound
[INFO] [stdout]     |
[INFO] [stdout] 10  | pub enum CircuitBreakerError<E: fmt::Display + Sync> {
[INFO] [stdout]     |                                              ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: `E` cannot be sent between threads safely
[INFO] [stdout]    --> src/circuitbreakers/mod.rs:9:24
[INFO] [stdout]     |
[INFO] [stdout] 9   | #[derive(Debug, Clone, Fail)]
[INFO] [stdout]     |                        ^^^^ `E` cannot be sent between threads safely
[INFO] [stdout]     | 
[INFO] [stdout]    ::: /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/failure-0.1.8/src/lib.rs:108:35
[INFO] [stdout]     |
[INFO] [stdout] 108 | pub trait Fail: Display + Debug + Send + Sync + 'static {
[INFO] [stdout]     |                                   ---- required by this bound in `failure::Fail`
[INFO] [stdout]     |
[INFO] [stdout]     = note: required because it appears within the type `CircuitBreakerError<E>`
[INFO] [stdout]     = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: consider further restricting this bound
[INFO] [stdout]     |
[INFO] [stdout] 10  | pub enum CircuitBreakerError<E: fmt::Display + Send> {
[INFO] [stdout]     |                                              ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: `E` doesn't implement `Debug`
[INFO] [stdout]    --> src/circuitbreakers/mod.rs:9:24
[INFO] [stdout]     |
[INFO] [stdout] 9   | #[derive(Debug, Clone, Fail)]
[INFO] [stdout]     |                        ^^^^ `E` cannot be formatted using `{:?}` because it doesn't implement `Debug`
[INFO] [stdout]     | 
[INFO] [stdout]    ::: /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/failure-0.1.8/src/lib.rs:108:27
[INFO] [stdout]     |
[INFO] [stdout] 108 | pub trait Fail: Display + Debug + Send + Sync + 'static {
[INFO] [stdout]     |                           ----- required by this bound in `failure::Fail`
[INFO] [stdout]     |
[INFO] [stdout]     = note: required because of the requirements on the impl of `Debug` for `CircuitBreakerError<E>`
[INFO] [stdout]     = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: consider further restricting this bound
[INFO] [stdout]     |
[INFO] [stdout] 10  | pub enum CircuitBreakerError<E: fmt::Display + Debug> {
[INFO] [stdout]     |                                              ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: `E` cannot be shared between threads safely
[INFO] [stdout]    --> src/bulkheads/mod.rs:12:24
[INFO] [stdout]     |
[INFO] [stdout] 12  | #[derive(Debug, Clone, Fail)]
[INFO] [stdout]     |                        ^^^^ `E` cannot be shared between threads safely
[INFO] [stdout]     | 
[INFO] [stdout]    ::: /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/failure-0.1.8/src/lib.rs:108:42
[INFO] [stdout]     |
[INFO] [stdout] 108 | pub trait Fail: Display + Debug + Send + Sync + 'static {
[INFO] [stdout]     |                                          ---- required by this bound in `failure::Fail`
[INFO] [stdout]     |
[INFO] [stdout]     = note: required because it appears within the type `BulkheadError<E>`
[INFO] [stdout]     = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: consider further restricting this bound
[INFO] [stdout]     |
[INFO] [stdout] 13  | pub enum BulkheadError<E: fmt::Display + Sync> {
[INFO] [stdout]     |                                        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: `E` cannot be sent between threads safely
[INFO] [stdout]    --> src/bulkheads/mod.rs:12:24
[INFO] [stdout]     |
[INFO] [stdout] 12  | #[derive(Debug, Clone, Fail)]
[INFO] [stdout]     |                        ^^^^ `E` cannot be sent between threads safely
[INFO] [stdout]     | 
[INFO] [stdout]    ::: /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/failure-0.1.8/src/lib.rs:108:35
[INFO] [stdout]     |
[INFO] [stdout] 108 | pub trait Fail: Display + Debug + Send + Sync + 'static {
[INFO] [stdout]     |                                   ---- required by this bound in `failure::Fail`
[INFO] [stdout]     |
[INFO] [stdout]     = note: required because it appears within the type `BulkheadError<E>`
[INFO] [stdout]     = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: consider further restricting this bound
[INFO] [stdout]     |
[INFO] [stdout] 13  | pub enum BulkheadError<E: fmt::Display + Send> {
[INFO] [stdout]     |                                        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: `E` doesn't implement `Debug`
[INFO] [stdout]    --> src/bulkheads/mod.rs:12:24
[INFO] [stdout]     |
[INFO] [stdout] 12  | #[derive(Debug, Clone, Fail)]
[INFO] [stdout]     |                        ^^^^ `E` cannot be formatted using `{:?}` because it doesn't implement `Debug`
[INFO] [stdout]     | 
[INFO] [stdout]    ::: /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/failure-0.1.8/src/lib.rs:108:27
[INFO] [stdout]     |
[INFO] [stdout] 108 | pub trait Fail: Display + Debug + Send + Sync + 'static {
[INFO] [stdout]     |                           ----- required by this bound in `failure::Fail`
[INFO] [stdout]     |
[INFO] [stdout]     = note: required because of the requirements on the impl of `Debug` for `BulkheadError<E>`
[INFO] [stdout]     = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: consider further restricting this bound
[INFO] [stdout]     |
[INFO] [stdout] 13  | pub enum BulkheadError<E: fmt::Display + Debug> {
[INFO] [stdout]     |                                        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 6 previous errors; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `stayalive`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error[E0277]: `E` cannot be shared between threads safely
[INFO] [stdout]    --> src/circuitbreakers/mod.rs:9:24
[INFO] [stdout]     |
[INFO] [stdout] 9   | #[derive(Debug, Clone, Fail)]
[INFO] [stdout]     |                        ^^^^ `E` cannot be shared between threads safely
[INFO] [stdout]     | 
[INFO] [stdout]    ::: /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/failure-0.1.8/src/lib.rs:108:42
[INFO] [stdout]     |
[INFO] [stdout] 108 | pub trait Fail: Display + Debug + Send + Sync + 'static {
[INFO] [stdout]     |                                          ---- required by this bound in `failure::Fail`
[INFO] [stdout]     |
[INFO] [stdout]     = note: required because it appears within the type `CircuitBreakerError<E>`
[INFO] [stdout]     = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: consider further restricting this bound
[INFO] [stdout]     |
[INFO] [stdout] 10  | pub enum CircuitBreakerError<E: fmt::Display + Sync> {
[INFO] [stdout]     |                                              ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: `E` cannot be sent between threads safely
[INFO] [stdout]    --> src/circuitbreakers/mod.rs:9:24
[INFO] [stdout]     |
[INFO] [stdout] 9   | #[derive(Debug, Clone, Fail)]
[INFO] [stdout]     |                        ^^^^ `E` cannot be sent between threads safely
[INFO] [stdout]     | 
[INFO] [stdout]    ::: /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/failure-0.1.8/src/lib.rs:108:35
[INFO] [stdout]     |
[INFO] [stdout] 108 | pub trait Fail: Display + Debug + Send + Sync + 'static {
[INFO] [stdout]     |                                   ---- required by this bound in `failure::Fail`
[INFO] [stdout]     |
[INFO] [stdout]     = note: required because it appears within the type `CircuitBreakerError<E>`
[INFO] [stdout]     = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: consider further restricting this bound
[INFO] [stdout]     |
[INFO] [stdout] 10  | pub enum CircuitBreakerError<E: fmt::Display + Send> {
[INFO] [stdout]     |                                              ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: `E` doesn't implement `Debug`
[INFO] [stdout]    --> src/circuitbreakers/mod.rs:9:24
[INFO] [stdout]     |
[INFO] [stdout] 9   | #[derive(Debug, Clone, Fail)]
[INFO] [stdout]     |                        ^^^^ `E` cannot be formatted using `{:?}` because it doesn't implement `Debug`
[INFO] [stdout]     | 
[INFO] [stdout]    ::: /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/failure-0.1.8/src/lib.rs:108:27
[INFO] [stdout]     |
[INFO] [stdout] 108 | pub trait Fail: Display + Debug + Send + Sync + 'static {
[INFO] [stdout]     |                           ----- required by this bound in `failure::Fail`
[INFO] [stdout]     |
[INFO] [stdout]     = note: required because of the requirements on the impl of `Debug` for `CircuitBreakerError<E>`
[INFO] [stdout]     = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: consider further restricting this bound
[INFO] [stdout]     |
[INFO] [stdout] 10  | pub enum CircuitBreakerError<E: fmt::Display + Debug> {
[INFO] [stdout]     |                                              ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: `E` cannot be shared between threads safely
[INFO] [stdout]    --> src/bulkheads/mod.rs:12:24
[INFO] [stdout]     |
[INFO] [stdout] 12  | #[derive(Debug, Clone, Fail)]
[INFO] [stdout]     |                        ^^^^ `E` cannot be shared between threads safely
[INFO] [stdout]     | 
[INFO] [stdout]    ::: /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/failure-0.1.8/src/lib.rs:108:42
[INFO] [stdout]     |
[INFO] [stdout] 108 | pub trait Fail: Display + Debug + Send + Sync + 'static {
[INFO] [stdout]     |                                          ---- required by this bound in `failure::Fail`
[INFO] [stdout]     |
[INFO] [stdout]     = note: required because it appears within the type `BulkheadError<E>`
[INFO] [stdout]     = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: consider further restricting this bound
[INFO] [stdout]     |
[INFO] [stdout] 13  | pub enum BulkheadError<E: fmt::Display + Sync> {
[INFO] [stdout]     |                                        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: `E` cannot be sent between threads safely
[INFO] [stdout]    --> src/bulkheads/mod.rs:12:24
[INFO] [stdout]     |
[INFO] [stdout] 12  | #[derive(Debug, Clone, Fail)]
[INFO] [stdout]     |                        ^^^^ `E` cannot be sent between threads safely
[INFO] [stdout]     | 
[INFO] [stdout]    ::: /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/failure-0.1.8/src/lib.rs:108:35
[INFO] [stdout]     |
[INFO] [stdout] 108 | pub trait Fail: Display + Debug + Send + Sync + 'static {
[INFO] [stdout]     |                                   ---- required by this bound in `failure::Fail`
[INFO] [stdout]     |
[INFO] [stdout]     = note: required because it appears within the type `BulkheadError<E>`
[INFO] [stdout]     = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: consider further restricting this bound
[INFO] [stdout]     |
[INFO] [stdout] 13  | pub enum BulkheadError<E: fmt::Display + Send> {
[INFO] [stdout]     |                                        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: `E` doesn't implement `Debug`
[INFO] [stdout]    --> src/bulkheads/mod.rs:12:24
[INFO] [stdout]     |
[INFO] [stdout] 12  | #[derive(Debug, Clone, Fail)]
[INFO] [stdout]     |                        ^^^^ `E` cannot be formatted using `{:?}` because it doesn't implement `Debug`
[INFO] [stdout]     | 
[INFO] [stdout]    ::: /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/failure-0.1.8/src/lib.rs:108:27
[INFO] [stdout]     |
[INFO] [stdout] 108 | pub trait Fail: Display + Debug + Send + Sync + 'static {
[INFO] [stdout]     |                           ----- required by this bound in `failure::Fail`
[INFO] [stdout]     |
[INFO] [stdout]     = note: required because of the requirements on the impl of `Debug` for `BulkheadError<E>`
[INFO] [stdout]     = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: consider further restricting this bound
[INFO] [stdout]     |
[INFO] [stdout] 13  | pub enum BulkheadError<E: fmt::Display + Debug> {
[INFO] [stdout]     |                                        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 6 previous errors; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "517dd3b6616a2cd66728a3de10c3dc3a277589ad02885eb3fa37db062c91cde8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "517dd3b6616a2cd66728a3de10c3dc3a277589ad02885eb3fa37db062c91cde8", kill_on_drop: false }`
[INFO] [stdout] 517dd3b6616a2cd66728a3de10c3dc3a277589ad02885eb3fa37db062c91cde8